Abseiling Unit with a Winding Function

ABSTRACT

The invention relates to an abseiling device having a winch function, comprising a guide roller ( 2 ) which is mounted so that it can rotate in both directions and is intended for the non-slip guidance of a rope element ( 15 ), a transmission mechanism with a centrifugal brake ( 7 ), the large gearwheel ( 4 ) of which mechanism is mounted securely against torque on a common shaft ( 3 ) with the guide roller ( 2 ), and a hand crank ( 8 ) for manually actuating the winch function, which acts on the drive shaft ( 6 ) of the small gearwheel ( 5 ) of the transmission mechanism. Positive locking of the abseiling device at a point which is less subject to loading and thus ensures greater safety is provided according to the invention by virtue of the common shaft ( 3 ) of the guide roller ( 2 ) and large gearwheel ( 4 ) being able to be locked positively.

The invention relates to an abseiling unit with a winding function according to the preamble of claim 1.

For rescuing persons from elevated locations, for example from burning high-rise buildings, from towers, scaffolding or the like, it is known to provide abseiling units for use at the elevated locations, in the case of which abseiling units the person to be rescued is secured to a traction means, for example a rope, which is guided in a non-slip fashion in the abseiling unit. When the traction means is loaded with the weight of the person to be rescued, the traction means runs over a guide roller of the abseiling unit, with a brake provided on the abseiling unit limiting the abseiling speed. As a result, it is possible for a person to abseil from an elevated location in a controlled fashion without external aid and without using their own physical strength. Abseiling units of said type often have a step-up transmission so as to provide a quickly rotating shaft which is connected to the brake, and a slowly rotating shaft which supports the guide roller.

An abseiling unit which can be suspended at a fixed location by means of a hook, and in which a traction rope, which is guided in a non-slip fashion over a guide roller, is braked by virtue of the guide roller being connected to a centrifugal brake by means of a step-up transmission, is known from DE 198 18 688 C1.

A lifting and rescuing unit (working unit with a winding function), in which the positive locking of a rope drum (guide roller) is provided by virtue of a latching bolt engaging in notches formed on the rope drum, is known from CH 364 180 A.

An abseiling unit mentioned above is known from DE 102 10 969 A1. Here, the quickly rotating shaft extends through a housing of the abseiling unit, and is provided with a hand crank. As a result, the quickly rotating shaft becomes a drive shaft. The abseiling unit is, as a result, augmented by an additional winding function which utilizes the step-up transmission ratio between the guide roller shaft and the braking and drive shaft. An abseiling unit which is augmented with a winding function in this way is significantly more versatile with regard to the situations which occur when rescuing persons. An assistant can thus initially utilize the winding function in order to pull up a person who has fallen into a shaft or onto a step situated at a lower level, and then abseil said person quickly and reliably by means of the abseiling function. There is also the option of a person lifting themselves up to an elevated location by virtue of the abseiling unit being fixed to the body of the person to be lifted, and being operated by the person themselves. Here, the abseiling function ensures constant safety should the person who is lifting themselves have an accident at the elevated location or during the lifting process. After releasing the hand crank, the person would then be abseiled by means of the abseiling function without them having to put in any more effort.

In both DE 102 10 969 A1 and CH 364 180 A, the hand crank and locking mechanism are in each case arranged on the same side of the transmission, at the output side of a single-stage spur gear transmission in DE 102 10 969 A1, and at the input side of a two-stage spur gear transmission in CH 364 180 A.

It is likewise known from DE 102 10 969 A1 that a blocking device, which acts on the quickly rotating drive shaft, is provided on the hand crank for the purpose of controlling the abseiling unit. Said device permits particularly favorable operation of the winding function since, by engaging a blocking bolt, the user can release the abseiling unit even when a load is hanging from it, without this resulting in the load being abseiled. The arrangement of the positive locking mechanism at the quickly rotating drive shaft results, however, in a high risk of wear, and therefore a grave safety problem, on account of the high rotational speeds at said device part.

A hand winder, in which a blocking catch enabling switch for hand winders having two blocking wheels, which are arranged adjacent to one another and provide retardation in opposite directions, is formed, is known from DE 177 841 A, in which, by throwing a shift lever into one or the other inclined position, one of the two blocking catches is engaged, and the other blocking catch is simultaneously disengaged. Here, the shift lever, which can be fixed into either inclined position, engages, by means of pins which are attached at both sides, into slots of the blocking catches, resulting in simultaneous engagement and disengagement of the catches.

The technical problem on which the invention is based is that of arranging a positive locking mechanism of the abseiling unit at a point which is less loaded and therefore ensures a greater degree of safety.

The invention achieves said object by means of an abseiling unit having the features of claim 1. Here, the functions of the hand crank and of the locking action are distributed between the input side and the output side. The arrangement of a positive locking device on the slowly rotating common shaft of the guide roller and the large gearwheel has the advantage that, in conventional designs of step-up transmissions, the rotational speed of said common shaft is approximately one order of magnitude lower than that of the drive shaft of the small gearwheel, and therefore the problem of wear is decisively reduced and the safety risk is eliminated.

In one particular embodiment, the locking action can be switched to act in either rotational direction. This has the advantage that the locking action can be changed between a winding function and an abseiling function by means of a simple hand grip, without it being necessary to release the unit. Said option is very helpful and advantageous, for example, in a situation in which the person to be rescued is hanging from the retaining rope prescribed by the occupational safety regulations.

In order to be able to decouple the retaining rope from the person to be rescued, the retaining rope must initially be relieved of the load (weight) of the person hanging from it. The winding function of the abseiling unit is utilized for this purpose.

Before the retaining rope is decoupled, the abseiling unit is positively locked in the winding function. The locking action can thereafter be switched to the abseiling function by means of a simple hand grip. In this way, the person to be rescued is automatically secured during the entire process of being decoupled from the retaining rope. The abseiling function of the abseiling unit can thereafter be enabled by releasing the locking action.

In one particularly advantageous embodiment, the switchable locking action is provided by means of a ratchet. In another embodiment which likewise meets the required safety conditions, the locking action is provided by means of a spring-loaded bolt.

The essence and the advantages of the device according to the invention are clarified by means of the exemplary embodiment illustrated in the appended drawing, in which:

FIG. 1 is a partially sectioned illustration of the abseiling unit, and

FIG. 2 shows the abseiling unit in a side view onto the side which faces away from the drive.

In FIG. 1, the locking device, in the form of a ratchet, is fixed in a torque-secure manner to the common shaft 3 of the guide roller 2 and the large gearwheel 4 at the left-hand side of the abseiling unit 1. The step-up transmission having the large gearwheel 4 and the small gearwheel 5, which is in the form of a pinion in the illustrated exemplary embodiment, is situated in the right-hand part of the housing. The centrifugal brake 7 is flanged onto the drive shaft 6 at the right-hand side.

The hand crank 8, which is fixed in a torque-secure manner to the drive shaft 6 which extends out of the housing, is illustrated at the far right-hand side. The handle 9 can be seen in the deployed position in the lower part of the hand crank 8. The handle 9 can be folded into the housing of the hand crank 8, so that in the abseiling function, the handle does not protrude out of the contour of the hand wheel, as a result of which the risk of injury, or the danger of imbalance being caused, which is relevant at the high rotational speeds which are possible, is eliminated.

The ratchet shaft 11, which is fixed to the common shaft 3 of the guide roller 2 and the large gearwheel 4 in a torque-secure manner, can be clearly seen in FIG. 2. The crown gear 16, into which the spring-loaded blocking catches 12 and 14 can engage, is fixed to the ratchet shaft 11. Here, blocking catch 12 acts against a counterclockwise rotation, while the blocking catch 14 acts against a clockwise rotation. As a result of the spring loading, the blocking catches automatically pivot into the teeth of the crown gear 16 if they are not deflected out of the engagement position by the switch 13.

LIST OF REFERENCE SIGNS

-   1 Abseiling unit -   2 Guide roller -   3 Common shaft -   4 Large gearwheel -   5 Small gearwheel -   6 Drive shaft -   7 Centrifugal brake -   8 Hand crank -   9 Handle -   10 Ratchet -   11 Ratchet shaft -   12 Spring-loaded blocking catch -   13 Rotational direction switch -   14 Spring-loaded blocking catch -   15 Traction means -   16 Crown gear 

1-4. (canceled)
 5. An abseiling unit for a traction cable, comprising a guide roller for non-slip guidance of said traction cable, the guide roller being rotatable in two rotational directions, a step-up transmission comprising a small gearwheel and a large gearwheel; and a hand crank for manually performing a winding function, wherein the hand crank engages on a drive shaft of the small gearwheel, wherein the large gearwheel is mounted in a torque-secure manner on a common shaft with the guide roller, and wherein a locking unit is provided for positively locking of said common shaft in at least one rotational direction.
 6. The abseiling unit as claimed in claim 5, wherein the locking unit can be switched to act in either rotational direction.
 7. The abseiling unit as claimed in claim 5, wherein the locking unit comprises a ratchet.
 8. The abseiling unit as claimed in claim 5, wherein the locking unit comprises a spring-loaded bolt.
 9. The abseiling unit as claimed in claim 5, further comprising a centrifugal brake, the centrifugal brake engaging the drive shaft of the small gearwheel.
 10. The abseiling unit as claimed in claim 5, wherein the small gearwheel and the large gearwheel intermesh each other.
 11. An abseiling unit for a traction cable, comprising a guide roller for non-slip guidance of said traction cable, the guide roller being rotatable in two rotational directions, a step-up transmission comprising a small gearwheel and a large gearwheel, and a hand crank for manually performing a winding function, wherein the hand crank engages on a drive shaft of the small gearwheel, wherein the large gearwheel is mounted in a torque-secure manner on a common shaft with the guide roller, wherein a locking unit is provided for positively locking of said step-up transmission in a loaded rotational direction, and wherein the step-up transmission is freely rotatable in a direction opposed to the loaded rotational direction.
 12. The abseiling unit as claimed in claim 11, wherein said locking unit is provided for positively locking one of said drive shaft and said common shaft.
 13. The abseiling unit as claimed in claim 12, wherein said locking unit is locking said common shaft.
 14. The abseiling unit as claimed in claim 11, wherein at least one of said drive shaft and said common shaft comprises a portion having a circumferential toothing, and wherein said locking unit can be engaged with said toothing.
 15. The abseiling unit as claimed in claim 11, wherein the locking unit can be switched to act in either rotational direction.
 16. The abseiling unit as claimed in claim 15, wherein the locking unit comprises a rotational direction switch for selectively engaging a blocking catch with one of said drive shaft and said common shaft.
 17. The abseiling unit as claimed in claim 11, wherein the locking unit comprises a ratchet.
 18. The abseiling unit as claimed in claim 11, wherein the step-up transmission is accommodated in a housing.
 19. The abseiling unit as claimed in claim 18, wherein said housing comprising a first housing part and a second housing part.
 20. The abseiling unit as claimed in claim 19, wherein the common shaft is partially arranged in each of said first housing part and said second housing part.
 21. The abseiling unit as claimed in claim 19, wherein the drive shaft is partially arranged in each of said first housing part and said second housing part.
 22. The abseiling unit as claimed in claim 19, wherein the large gearwheel and the small gearwheel are arranged in the same of said first housing part and said second housing part.
 23. The abseiling unit as claimed in claim 19, wherein said first housing part and said second housing part are assembled using at least one screw.
 24. The abseiling unit as claimed in claim 11, further comprising a suspended support bracket.
 25. The abseiling unit as claimed in claim 11, further comprising a centrifugal brake, the centrifugal brake engaging the drive shaft of the small gearwheel.
 26. An abseiling unit for an abseiling cable, comprising a housing rotatably accommodating a first shaft and a second shaft, wherein a first gearwheel and a centrifugal brake are arranged on said first shaft, wherein a second gearwheel and a pulley are arranged on said second shaft, said first gearwheel intermeshing with said second gearwheel, at least one of said first shaft and said second shaft protruding out of said housing for coupling to a torque transmitting element, wherein said pulley comprises a circumferential groove for slip-free receiving said abseiling cable, wherein the housing comprises at least one opening for the passage of said abseiling cable, wherein a locking unit is provided for positively locking one of said first shaft and said second shaft in one of a first rotational direction and a second rotational direction, while said pulley is freely rotatable in the other of said first rotational direction and said second rotational direction, such that a load can freely be lifted up using said abseiling cable while the abseiling cable is secured against a downward movement under said load.
 27. The abseiling unit as claimed in claim 26, wherein said locking unit comprises a first engagement portion and a second engagement portion, said first engagement portion and said second engagement portion alternatively engaging a toothed portion of said one of said first shaft and said second shaft.
 28. The abseiling unit as claimed in claim 26, wherein said locking unit is coupled to a protruding portion of one of said first shaft and said second shaft. 